Tube depth marking tool



FIG. 1 is a front elevational view of a tube depth marking tool in accordance with the present design;

FIG. 2 is a back elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a side elevational view thereof;

FIG. 6 is an opposite side elevational view thereof; and,

FIG. 7 is an isometric view thereof.

The broken lines depict portions of the tube depth marking tool in which the design is embodied that are not considered part of the claimed design. 

CLAIM The ornamental design for a tube depth marking tool, as shown. 